Bi-planar instrument for bone cutting and joint realignment procedure

ABSTRACT

A technique for correcting a bone deformity, such as a bunion, may be performed using an instrument that defines a spacer body connected to a fulcrum. The spacer body portion of the instrument can be inserted into a joint space between opposed bone ends. The fulcrum body can be inserted between adjacent metatarsals. An angle set between the spacer body and fulcrum body can help properly position both features within different joint spaces for ensuring that subsequent steps of the surgical procedure are properly performed and instrumentation is appropriately aligned.

CROSS-REFERENCE

This application is a divisional of U.S. patent application Ser. No.16/987,916, filed Aug. 7, 2020, which claims the benefit of U.S.Provisional Patent Application No. 62/883,649, filed Aug. 7, 2019. Theentire contents of both of these applications are incorporated herein byreference.

TECHNICAL FIELD

This disclosure relates to surgical devices and, more particularly, tosurgical devices for assisting in bone cutting and/or realignmenttechniques.

BACKGROUND

Bones within the human body, such as bones in the foot, may beanatomically misaligned. For example, one common type of bone deformityis hallux valgus, which is a progressive foot deformity in which thefirst metatarsophalangeal joint is affected and is often accompanied bysignificant functional disability and foot pain. The metatarsophalangealjoint is medially deviated, resulting in an abduction of the firstmetatarsal while the phalanges adduct. This often leads to developmentof soft tissue and a bony prominence on the medial side of the foot,which is called a bunion.

Surgical intervention may be used to correct a bunion deformity. Avariety of different surgical procedures exist to correct buniondeformities and may involve removing the abnormal bony enlargement onthe first metatarsal and/or attempting to realign the first metatarsalrelative to the adjacent metatarsal. Surgical instruments that canfacilitate efficient, accurate, and reproducible clinical results areuseful for practitioners performing bone realignment techniques.

SUMMARY

In general, this disclosure is directed to an instrument that can beused in a surgical bone cutting and/or realignment procedure. Theinstrument can include a spacer body connected to a fulcrum body. Thespacer body and fulcrum body may be positionable in adjacent jointspaces, with a connecting member between the spacer body and fulcrumbody helping to control the relative position of the spacer body andfulcrum body when inserted into respective joint spaces.

For example, the spacer body can be positioned in a joint space betweenopposed bone ends, such as a joint space between a metatarsal and anopposed cuneiform. In some implementations, the metatarsal is a firstmetatarsal and the opposed cuneiform is a medial cuneiform. In eithercase, the spacer body may define a first portion positionable in thejoint space between opposed bone ends and a second portion that extendsabove (e.g., dorsally) from the joint space. The second portion of thespacer body can be connected to a bone preparation guide. The bonepreparation guide may be removable from and engageable with the spacerbody (e.g., by inserting the bone preparation guide on the spacer bodyafter the spacer body is inserted into the joint space). Alternatively,the bone preparation guide can be permanently coupled to the spacer body(e.g., to define a unitary structure). In either case, the bonepreparation guide may define one or more guide surfaces for guiding abone preparation instrument to prepare the ends of adjacent bones (e.g.,to prepare an end of the metatarsal and/or an end of the opposedcuneiform). For example, the bone preparation guide may define at leastone cutting slot positioned over the metatarsal for guiding a saw bladeto cut an end of the metatarsal and at least one cutting slot positionedover the opposed cuneiform for guiding a saw blade to cut an end of theopposed cuneiform.

The instrument also includes a fulcrum body coupled to the spacer body.The fulcrum body may be configured (e.g., sized and/or shaped) to bepositioned in an intermetatarsal space between adjacent metatarsals,such as in the intermetatarsal space between the first metatarsal andthe second metatarsal. The fulcrum body may define a fulcrum, or pivotsurface, about which the metatarsal can rotate to realign a position ofthe metatarsal relative to the opposing cuneiform and/or adjacentmetatarsal. For example, the fulcrum body may define a pivot surfaceabout which a proximal base of the metatarsal can pivot as anintermetatarsal angle is closed between the metatarsal and the adjacentmetatarsal. This may help prevent the base of the metatarsal fromshifting laterally, such as by compressing against the adjacentmetatarsal, as the metatarsal is realigned.

In some configurations, the spacer body is coupled to the fulcrum bodywith a bridge member. The bridge member may transition from one plane(e.g., generally in the frontal plane) in which the spacer body ispositioned to a second plane (e.g., generally in the sagittal plane) inwhich the fulcrum body is positioned. For example, the bridge member maydefine a corner (e.g., with an interior angle ranging from 60 degrees to120 degrees, such as from 80 degrees to 100 degrees, or approximately 90degrees) operatively connecting the spacer body to the fulcrum body. Inuse, the bridge member can be positioned against a corner of themetatarsal being realigned, such as a proximal-lateral corner/surface ofthe metatarsal. When so positioned, the spacer body may be positioned inthe joint space between the metatarsal and opposed cuneiform while thefulcrum body may be positioned in the joint space between the metatarsaland adjacent metatarsal. The bridge member may help establish a fixedposition between the spacer body and fulcrum body and/or prevent thespacer body and fulcrum body from shifting relative to each other and/orin their respective joint spaces during the surgical procedure. This canhelp ensure that the spacer body and fulcrum body are appropriatelypositioned for subsequent procedure steps performed using the spacerbody and fulcrum body (e.g., performing a bone preparation step using abone preparation guide attached to the spacer body and/or realigning ametatarsal by pivoting about the fulcrum body).

In one example, a bi-planar instrument for a bone cutting and jointrealignment procedure is described. The instrument includes a spacerbody configured to be inserted into a joint space between a metatarsaland an opposed cuneiform of a foot. The instrument also includes afulcrum body coupled to the spacer body, the fulcrum body beingconfigured to be inserted in an intermetatarsal space between themetatarsal and an adjacent metatarsal.

In another example, a method is described that includes inserting aspacer body into a joint space between a metatarsal and an opposedcuneiform of a foot. The method also includes inserting a fulcrum bodycoupled to the spacer between the metatarsal and an adjacent metatarsal.The method further involves preparing an end of the metatarsal using abone preparation guide aligned with the spacer to guide a bonepreparation instrument and preparing an end of the opposing cuneiformusing the bone preparation guide to guide a bone preparation instrument.In addition, the method includes moving the metatarsal relative to theadjacent metatarsal in at least a transverse plane, thereby pivoting themetatarsal about the fulcrum body and reducing an intermetatarsal anglebetween the metatarsal and the adjacent metatarsal.

The details of one or more examples are set forth in the accompanyingdrawings and the description below. Other features, objects, andadvantages will be apparent from the description and drawings, and fromthe claims.

BRIEF DESCRIPTION OF DRAWINGS

FIGS. 1A and 1B are front views of a foot showing a normal firstmetatarsal position and an example frontal plane rotational misalignmentposition, respectively.

FIGS. 2A and 2B are top views of a foot showing a normal firstmetatarsal position and an example transverse plane misalignmentposition, respectively.

FIGS. 3A and 3B are side views of a foot showing a normal firstmetatarsal position and an example sagittal plane misalignment position,respectively.

FIGS. 4A and 4B are perspective and top views, respectively, of anexample bone positioning operation in which a bi-planar instrument ispositioned in a first joint space and an intersecting second jointspace.

FIGS. 5A and 5B are perspective and top views, respectively, of anexample configuration of the bi-planar instrument of FIGS. 4A and 4B.

FIGS. 5C and 5D are perspective and sectional views, respectively,showing an example configuration of a fulcrum body defining a concavebone contacting surface.

FIGS. 5E and 5F are perspective and sectional views, respectively,showing an example configuration of a fulcrum body defining a convexbone contacting surface.

FIGS. 6A and 6B are perspective and top views, respectively showing anexample bone preparation guide that may be used as part of a surgicalprocedure involving a bi-planar instrument.

FIGS. 7A and 7B are perspective and top views, respectively, of anexample configuration of a bi-planar instrument in which a spacer bodyis detachable from and attachable to a fulcrum body.

FIGS. 8A and 8B are front and rear perspective views, respectively, ofan example configuration of a bi-planar instrument configured with ahinged connection.

FIGS. 9A-9D illustrate example relative rotational positions between aspacer body and a fulcrum body for the example bi-planar instrumentillustrated in FIGS. 8A and 8B.

FIGS. 10A-10C are illustrations of an example system that includes abi-planar instrument and a bone preparation guide, where the bonepreparation guide is sized to move relative to the spacer body of thebi-planar instrument.

DETAILED DESCRIPTION

In general, the present disclosure is directed to an instrument thatincludes a spacer body and fulcrum body that can be used in a surgicalprocedure, such as bone realignment procedure. Example procedures inwhich the fulcrum structures may be used include a bone alignment,osteotomy, fusion procedure, and/or other procedures where one or morebones are operated upon and/or realigned relative to one or more otherbones. Such a procedure can be performed, for example, on bones (e.g.,adjacent bones separated by a joint or different portions of a singlebone) in the foot or hand, where bones are relatively smaller comparedto bones in other parts of the human anatomy. In one example, aprocedure utilizing an instrument that includes two bodies joinedtogether by a bridge member can be performed to correct an alignmentbetween a metatarsal (e.g., a first metatarsal) and a second metatarsaland/or a cuneiform (e.g., a medial, or first, cuneiform), such as in abunion correction surgery. An example of such a procedure is a Lapidusprocedure (also known as a first tarsal-metatarsal fusion). While theexample instruments of the disclosure are generally described as beinguseful for insertion into a space between opposed bone endstransitioning into an intermetatarsal space, the instruments may be usedin any desired application and the disclosure is not limited in thisrespect.

FIGS. 1-3 are different views of a foot 200 showing example anatomicalmisalignments that may occur and be corrected using a fulcrum accordingto the present disclosure. Such misalignment may be caused by a halluxvalgus (bunion), natural growth deformity, or other condition causinganatomical misalignment. FIGS. 1A and 1B are front views of foot 200showing a normal first metatarsal position and an example frontal planerotational misalignment position, respectively. FIGS. 2A and 2B are topviews of foot 200 showing a normal first metatarsal position and anexample transverse plane misalignment position, respectively. FIGS. 3Aand 3B are side views of foot 200 showing a normal first metatarsalposition and an example sagittal plane misalignment position,respectively. While FIGS. 1B, 2B, and 3B show each respective planarmisalignment in isolation, in practice, a metatarsal may be misalignedin any two of the three planes or even all three planes. Accordingly, itshould be appreciated that the depiction of a single plane misalignmentin each of FIGS. 1B, 2B, and 3B is for purposes of illustration and ametatarsal may be misaligned in multiple planes that is desirablycorrected.

With reference to FIGS. 1A and 2A, foot 200 is composed of multiplebones including a first metatarsal 210, a second metatarsal 212, a thirdmetatarsal 214, a fourth metatarsal 216, and a fifth metatarsal 218. Themetatarsals are connected distally to phalanges 220 and, moreparticularly, each to a respective proximal phalanx. The firstmetatarsal 210 is connected proximally to a medial cuneiform 222, whilethe second metatarsal 212 is connected proximally to an intermediatecuneiform 224 and the third metatarsal is connected proximally tolateral cuneiform 226. The fourth and fifth metatarsals 216, 218 areconnected proximally to the cuboid bone 228. The joint 230 between ametatarsal and respective cuneiform (e.g., first metatarsal 210 andmedial cuneiform 222) is referred to as the tarsometatarsal (“TMT”)joint. The joint 232 between a metatarsal and respective proximalphalanx is referred to as a metatarsophalangeal joint. The angle 234between adjacent metatarsals (e.g., first metatarsal 210 and secondmetatarsal 212) is referred to as the intermetatarsal angle (“IMA”).

As noted, FIG. 1A is a frontal plane view of foot 200 showing a typicalposition for first metatarsal 210. The frontal plane, which is alsoknown as the coronal plane, is generally considered any vertical planethat divides the body into anterior and posterior sections. On foot 200,the frontal plane is a plane that extends vertically and isperpendicular to an axis extending proximally to distally along thelength of the foot. FIG. 1A shows first metatarsal 210 in a typicalrotational position in the frontal plane. FIG. 1B shows first metatarsal210 with a frontal plane rotational deformity characterized by arotational angle 236 relative to ground, as indicated by line 238.

FIG. 2A is a top view of foot 200 showing a typical position of firstmetatarsal 210 in the transverse plane. The transverse plane, which isalso known as the horizontal plane, axial plane, or transaxial plane, isconsidered any plane that divides the body into superior and inferiorparts. On foot 200, the transverse plane is a plane that extendshorizontally and is perpendicular to an axis extending dorsally toplantarly (top to bottom) across the foot. FIG. 2A shows firstmetatarsal 210 with a typical IMA 234 in the transverse plane. FIG. 2Bshows first metatarsal 210 with a transverse plane rotational deformitycharacterized by a greater IMA caused by the distal end of firstmetatarsal 210 being pivoted medially relative to the second metatarsal212.

FIG. 3A is a side view of foot 200 showing a typical position of firstmetatarsal 210 in the sagittal plane. The sagittal plane is a planeparallel to the sagittal suture which divides the body into right andleft halves. On foot 200, the sagittal plane is a plane that extendsvertically and is perpendicular to an axis extending proximally todistally along the length of the foot. FIG. 3A shows first metatarsal210 with a typical rotational position in the sagittal plane. FIG. 3Bshows first metatarsal 210 with a sagittal plane rotational deformitycharacterized by a rotational angle 240 relative to ground, as indicatedby line 238.

A bi-planar instrument according to the disclosure can define a spacerbody extending a medial to lateral direction (e.g., parallel to thefrontal plane) of the foot that is coupled to a fulcrum body extendingin a proximal to distal direction (e.g., parallel to sagittal plane) ofthe foot. A connecting member can couple the spacer body to the fulcrumbody and transition from the frontal plane to the sagittal plane. Insome examples, the connecting member can conform to (e.g., contact) aregion of the metatarsal being realigned on the proximal end face of themetatarsal and also on a proximal end of a lateral side of themetatarsal. The bi-planar instrument can be used as part of a bonepositioning technique to correct an anatomical misalignment of a bone orbones. In some applications, the technique involves realigning ametatarsal relative to an adjacent cuneiform and/or adjacent metatarsal.The metatarsal undergoing realignment may be anatomically misaligned inthe frontal plane, transverse plane, and/or sagittal plane, asillustrated and discussed with respect to FIGS. 1-3 above. Accordingly,realignment may involve releasing the misaligned metatarsal or portionthereof for realignment and thereafter realigning the metatarsal in oneor more planes, two or more planes, or all three planes. After suitablyrealigning the metatarsal, the metatarsal can be fixated to hold andmaintain the realigned positioned.

While a metatarsal can have a variety of anatomically aligned andmisaligned positions, in some examples, the term “anatomically alignedposition” means that an angle of a long axis of first metatarsal 210relative to the long axis of second metatarsal 212 is about 10 degreesor less in the transverse plane and/or sagittal plane. In certainembodiments, anatomical misalignment can be corrected in both thetransverse plane and the frontal plane. In the transverse plane, anormal IMA 234 between first metatarsal 210 and second metatarsal 212 isless than about 9 degrees. An IMA 234 of between about 9 degrees andabout 13 degrees is considered a mild misalignment of the firstmetatarsal and the second metatarsal. An IMA 234 of greater than about16 degrees is considered a severe misalignment of the first metatarsaland the second metatarsal.

In some applications, a bi-planar instrument is used as part of arealignment technique to anatomically align first metatarsal 210 or aportion thereof by reducing the IMA from over 10 degrees to about 10degrees or less (e.g., to an IMA of about 1-5 degrees), including tonegative angles of about −5 degrees or until interference with thesecond metatarsal, by positioning the first metatarsal at a differentangle with respect to the second metatarsal.

With respect to the frontal plane, a normal first metatarsal will bepositioned such that its crista prominence is generally perpendicular tothe ground and/or its sesamoid bones are generally parallel to theground and positioned under the metatarsal. This position can be definedas a metatarsal rotation of 0 degrees. In a misaligned first metatarsal,the metatarsal is axially rotated between about 4 degrees to about 30degrees or more. In some embodiments, a bi-planar instrument is used aspart of a realignment technique to anatomically align the metatarsal byreducing the metatarsal rotation from about 4 degrees or more to lessthan 4 degrees (e.g., to about 0 to 2 degrees) by rotating themetatarsal with respect to the medial cuneiform.

A bi-planar instrument that defines a spacer body coupled to a fulcrumbody according to the disclosure may be useful to provide a unitarystructure (e.g., prior to or after being assembled) that can bepositioned between two adjacent, intersecting joint spaces: a firstjoint space between opposed ends of a metatarsal and cuneiform and anintermetatarsal space between adjacent metatarsals. The spacer body caninclude a first portion insertable into the joint space and a secondportion that projects above the joint space. The second portionprojecting above the joint space can be coupled to a bone preparationguide, thereby facilitating positioning of the bone preparation guideover the metatarsal and/or cuneiform between which the spacer body ispositioned. The fulcrum body can establish and/or maintain space betweenadjacent bones being moved, preventing lateral translation or base shiftof the bones during rotation and/or pivoting.

For example, the bi-planar instrument can include a spacer bodypositionable in the joint space between first metatarsal 210 and medialcuneiform 222. The spacer body can be coupled to a bone preparationguide. The bone preparation guide may include a receiving slot intowhich a projecting end of the spacer body is positioned, therebyorienting the bone preparation guide relative to the joint space via thespacer body positioned therein. The bone preparation guide may includeat least one cutting slot positioned over an end of first metatarsal 210and/or an end of medial cuneiform 222 to be cut, such as at least onemetatarsal side cutting slot positionable over an end of firstmetatarsal 210 to be cut and at least one cuneiform cutting slotpositionable over an end of medial cuneiform 222 to be cut.

The bi-planar instrument can also include a fulcrum body positionable ina joint space between first metatarsal 210 and second metatarsal 212.The fulcrum body can be inserted in the notch between first metatarsal210 and second metatarsal 212 at the base of the metatarsals (e.g.,adjacent respective cuneiforms) before moving the first metatarsal,e.g., to help avoid the proximal-most base of the first metatarsal 210from shifting toward the proximal-most base of the second 212. Thefulcrum body can provide a point about which first metatarsal 210 canrotate and/or pivot while helping minimize or avoid base compressionbetween the first metatarsal and the second metatarsal. In addition, useof the fulcrum body may cause first metatarsal 210 and medial cuneiform222 to be better angled relative to guide slots positioned over the endfaces of the bones (of the bone preparation guide engaged with thespacer body), providing a better cut angle through the guide slots thanwithout use of the fulcrum body. This can help reduce or eliminateunwanted spring-back, or return positioning, of first metatarsal 210after initial realignment of the metatarsal.

FIGS. 4A and 4B (referred to collectively as FIG. 4 ) are perspectiveand top views, respectively, of an example bone positioning operation inwhich a bi-planar instrument 10 is positioned in a first joint space andan intersecting second joint space, where a bone forming the first andsecond joint spaces is being realigned relative to one or more adjacentbones. In particular, FIG. 4 illustrates a bi-planar instrument 10having a spacer body 12 coupled to a fulcrum body 14 via a connecting orbridge member 16. Spacer body 12 is positioned at an intersectionbetween an end of first metatarsal 210 and opposed medial cuneiform 222.Fulcrum body 14 is positioned between first metatarsal 210 and secondmetatarsal 212. Bi-planar instrument 10 may optionally be used inconjunction with other surgical devices, such as a bone positioningguide 20 and a bone preparation guide 30 (FIG. 6 ). Additional detailson example bone positioning guides, bone preparation guides, and relatedtechniques are described in U.S. patent application Ser. No. 14/981,335,filed Dec. 28, 2015, and U.S. patent application Ser. No. 15/236,464,filed Aug. 14, 2016, the entire contents of which are incorporatedherein by reference.

As shown in the example of FIG. 4 , spacer body 12 can be positionedbetween opposed end of adjacent bones, such as opposed ends of ametatarsal (e.g., first metatarsal 210) and cuneiform (e.g., medialcuneiform 222) separated by a joint space. Spacer body 12 can define alength configured to be inserted into the joint space between the twobones (e.g., with at least a portion of the body projecting dorsallyabove the joint space), a thickness configured to extend between themetatarsal and the opposed cuneiform (e.g., with first metatarsal 210and medial cuneiform 222 contacting opposed sides of the spacer body),and a width configured to extend in a medial to lateral direction acrossthe foot.

Spacer body 12 can be positioned at any suitable location across thejoint space (e.g., in the front plane). The specific positioning ofspacer body 12 in use may be established by bridge member 16 coupled tofulcrum body 14. For example, when bi-planar instrument 10 is insertedinto the joint space, bridge member 16 may contact a proximal-lateralcorner or region of first metatarsal 210. This can limit the extent towhich spacer body 12 can shift medially across the joint space, helpingto fix the spacer body in the medial to lateral direction (e.g., in thefrontal plane). In other examples, bi-planar instrument 10 can beinserting into the joint space without the corner defined by bridgemember 16 contacting a bone (e.g., first metatarsal).

Although not illustrated in FIG. 4 , in different examples, spacer body12 can be engageable with and separable from bone preparation guide 30or may be integral with (e.g., permanently coupled to) the bonepreparation guide. The positioning of spacer body 12 in the joint spacecan dictate the positioning of bone preparation guide 30 coupled theretoand, correspondingly, the guiding of a bone preparation instrumentfacilitated by the bone preparation guide.

Bi-planar instrument 10 also includes fulcrum body 14. Fulcrum body 14may be positioned distally of a bone positioning guide 20 between firstmetatarsal 210 and second metatarsal 212 or, in other applications,distally of the guide. As illustrated, fulcrum body 14 of bi-planarinstrument 10 is shown proximally of bone positioning guide 20, with thefulcrum body being positioned in the joint space between the firstmetatarsal and second metatarsal (e.g., at the ends of the first andsecond metatarsals abutting the medial and intermediate cuneiform bones,respectively). In still other examples, fulcrum body 14 can bepositioned in the intermetatarsal space between first metatarsal 210 andsecond metatarsal 212 without using bone positioning guide 20 and/orbone preparation guide 30 (FIG. 6 ).

In use, the clinician can insert fulcrum body 16 between firstmetatarsal 210 and second metatarsal 212 (or other adjacent bones, whennot performing a metatarsal realignment) at any time prior to moving thefirst metatarsal (e.g., by actuating bone positioning guide 20 or othermeans of manipulating the bone). In one embodiment, the clinicianprepares the joint being operated upon to release soft tissues and/orexcise the plantar flare from the base of the first metatarsal 210.Either before or after installing bone positioning guide 20 overadjacent bones, the clinician inserts bi-planar instrument 10 in thejoint spaces. The clinician can insert spacer body 12 in the joint spacebetween first metatarsal 210 and medial cuneiform 222 and also insertfulcrum body 14 in the joint space between first metatarsal 210 andsecond metatarsal 212.

After inserting bi-planar instrument 10, the clinician can actuate bonepositioning guide 20. In the case of a left foot as shown in FIG. 4 ,actuation of bone positioning guide 20 causes the first metatarsal 210to rotate counterclockwise in the frontal plane (from the perspective ofa patient) and also pivot in the transverse plane about the fulcrumbody. In the case of a right foot (not shown), actuation causes thefirst metatarsal to rotate clockwise in the frontal plane (from theperspective of a patient) and also pivot in the transverse plane aboutthe fulcrum. Thus, for both feet, actuation of bone positioning guide 20can supinate the first metatarsal in the frontal plane and pivot thefirst metatarsal in the transverse plane about fulcrum body 14.

Before or after actuating bone positioning guide 20 (when used), theclinician can engage a bone preparation guide with a portion of spacerbody 12 projecting from the joint space between first metatarsal 210 andmedial cuneiform 222. Spacer body 12 may have a length effective toengage a bone preparation guide thereto. In some implementations, theclinician installs a separate, removable bone preparation guide 30 ontospacer body 12 after inserting bi-planar instrument 10 into the jointspaces. The clinician can attach the bone preparation guide 30 before orafter attaching bone positioning guide 20. The clinician can use bonepreparation guide 30 to guide a bone preparation instrument, such as acutting blade, to prepare an end of first metatarsal 210 and an opposedend of medial cuneiform 222. The clinician can prepare one or both endsof the bones before and/or after engaging bone preparation guide 20 tomove first metatarsal 210 in at least one plane, such as the transverseplane and/or frontal plane.

FIGS. 5A and 5B (collectively referred to as FIG. 5 ) are perspectiveand top views, respectively, of an example configuration of bi-planarinstrument 10. As shown in this example, instrument 10 includes spacerbody 12 coupled to fulcrum body 14. In some examples, spacer body 12 andfulcrum body 14 are intersecting body members coupled together withoutan intervening coupling member. In other examples, such as the exampleillustrated in FIG. 5 , an intermediate coupling member 16 joins spacerbody 12 to fulcrum body 14.

Coupling member 16 may be in the form of a bridge extending betweenspacer body 12 and fulcrum body 14. In use, spacer body 12 may beconfigured to extend in a frontal plane of the foot, between firstmetatarsal 210 and medial cuneiform 222. Fulcrum body 14 may beconfigured to extend in a sagittal plane of the foot, between firstmetatarsal 210 and second metatarsal 212. Bridge member 16 can define abended and/or angled region of bi-planar instrument 10 that transitionsfrom the frontal plane to the sagittal plane. For example, bridge membermay be configured to extend from a proximal side of first metatarsal 210to a lateral side of the metatarsal. By coupling spacer body 12 tofulcrum body 14 via bridge member 16, the position and orientation ofthe two bodies relative to each other and/or relative to firstmetatarsal 210 may be fixed. This can help ensure the proper positioningof the respective bodies in use.

In general, spacer body 12 may define a length configured to be insertedinto the joint space, a thickness configured to extend between the bonedefining the joint space (e.g., metatarsal and the opposed cuneiform),and a width configured to extend in a medial to lateral directionpartially or fully across the joint space. Spacer body 12 may define afirst portion 40 configured to extend at least partially into the jointspace between the metatarsal and the opposed cuneiform and a secondportion 42 configured to extend above the joint space. Second portion 42can be configured to engage a receiving cavity of a bone preparationguide or can be integrally attached to the bone preparation guide.

Fulcrum body 14 can define a length configured to be inserted into theintermetatarsal space, a thickness configured to extend between firstmetatarsal 210 and second metatarsal 212, and a width configured toextend in the proximal to distal direction across the foot. Thethickness of fulcrum body 14 may be tapered toward the leading end tofacilitate insertion of fulcrum body 14 into a space between adjacentmetatarsals.

In some examples, instrument 10 includes a handle 44. Handle 44 isillustrated as being operatively connected to fulcrum body 14 althoughcan be connected to and extend from spacer body 12 in addition to or inlieu of fulcrum body 14. Handle 44 may be any structure projectingproximally from bi-planar instrument 10 (e.g., from fulcrum body 14)that can provide a gripping location for the instrument during use. Insome examples, such as the example illustrated in FIG. 5 , handle 44 canproject angularly away from fulcrum body 14 to define a tissueretraction space.

The tissue retraction space may be a region bounded on one side byfulcrum body 14 and one side of handle 44. In use, body fulcrum 14 maybe inserted into an intermetatarsal space with handle 44 extending outof the surgical incision and over an epidermal layer with tissuecaptured in the tissue retraction space. For example, fulcrum body 14may be inserted into an intermetatarsal space with handle 44 projectingtoward the lateral side of the foot being operated upon. The tissueretraction space may help retract tissue and push the tissue laterallyaway from a first metatarsal and/or medial cuneiform being operatedupon.

To form a tissue retraction space, handle 44 may project away fromfulcrum body 14, e.g., linearly at a zero-degree angle and/or laterallyat a non-zero-degree angle. The specific angular orientation of thehandle 44 relative to the body 14 may vary. However, in some examples,handle 44 is oriented relative to the fulcrum body 14 so a handle axisintersects an axis extending along the length of the fulcrum body at anacute angle ranging from 5 degrees to 85 degrees, such as from 20degrees to 75 degrees, or from 35 degrees to 55 degrees.

In general, bi-planar instrument 10 can be fabricated from any suitablematerials. In different examples, the instrument may be fabricated frommetal, a polymeric material, or a hybrid form of multiple metals and/orpolymeric materials. In addition, although spacer body 12 and fulcrumbody 14 are generally illustrated as having rectangular cross-sectionalshapes, one or both bodies can define a different generally polygonalcross-sectional shape (e.g., square, hexagonal) and/or generally arcuatecross-sectional shape (e.g., circular, elliptical).

For example, while spacer body 12 and/or fulcrum body 14 may define aplanar face contacting a bone, one or both bodies may alternatively havenon-planar faces contacting the bone. FIGS. 5C and 5D are perspectiveand sectional views, respectively, showing an example configuration offulcrum body 14 defining a concave bone contacting surface. FIGS. 5E and5F are perspective and sectional views, respectively, showing an exampleconfiguration of fulcrum body 14 defining a convex bone contactingsurface.

As still another example, fulcrum body 14 of bi-planar instrument 10 maybe angled in the sagittal plane, e.g., such that the plantar end of thefulcrum body extends farther medially than the dorsal end of the fulcrumbody or, alternatively, the plantar end of the fulcrum body extendfarther laterally than the dorsal end of the fulcrum body. Anglingfulcrum body 14 in the sagittal plane may be useful to help dorsiflex orplantarflex the metatarsal being moved, e.g., by providing an angledfulcrum surface tending to redirect the metatarsal in the sagittalplane. The foregoing discussion of example fulcrum body shape and/orprofile configurations can be employed in a standalone fulcrum device inthe techniques described herein (e.g., without using an attached spacerbody).

In some examples, bi-planar instrument 10 (e.g., spacer body 12, fulcrumbody 14, bridge member 16) will be formed as a unitary structure, e.g.,by milling, casting, or molding the components to be permanently andstructurally integrated together. In other examples, one or more thefeatures may be fabricated as separate components that are subsequentlyjoined together.

In some examples, bi-planar instrument 10 is used as part of ametatarsal realignment procedure in which a metatarsal is realignedrelative to an adjacent cuneiform and/or metatarsal in one or moreplanes, such as two or three planes. Additional details on example bonerealignment techniques and devices with which instrument 10 may be usedare described in U.S. Pat. No. 9,622,805, titled “BONE POSITIONING ANDPREPARING GUIDE SYSTEMS AND METHODS,” filed on Dec. 28, 2015 and issuedApr. 18, 2017, and U.S. Pat. No. 9,936,994, titled “BONE POSITIONINGGUIDE,” filed on Jul. 14, 2016 and issued on Apr. 10, 2018, and USPatent Publication No. 2017/0042599 titled “TARSAL-METATARSAL JOINTPROCEDURE UTILIZING FULCRUM,” filed on Aug. 14, 2016. The entirecontents of each of these documents are hereby incorporated byreference.

FIGS. 6A and 6B (collectively referred to as FIG. 6 ) are perspectiveand top views, respectively showing an example bone preparation guide 30that may be used as part of a surgical procedure involving bi-planarinstrument 10. In some examples, bone preparation guide 30 includes abody 32 defining a first guide surface 34 to define a first preparingplane and a second guide surface 36 to define a second preparing plane.A tissue removing instrument (e.g., a saw, rotary bur, osteotome, etc.,not shown) can be aligned with the surfaces to remove tissue (e.g.,remove cartilage or bone and/or make cuts to bone). The first and secondguide surfaces 34, 36 can be spaced from each other by a distance,(e.g., between about 2 millimeters and about 10 millimeters, such asbetween about 4 and about 7 millimeters). In different configurations,the first and second guide surfaces can be parallel to each other orangled relative to each other, such that cuts to adjacent bones usingthe guide surfaces will be generally parallel or angled relative to eachother.

In some configurations, the first and second guide surfaces 34, 36 arebounded by opposed surfaces to define guide slots. Each slot can besized to receive a tissue removing instrument to prepare the bone ends.In either case, an opening 38 may be defined in body 32 of bonepreparation guide 30 for receiving spacer body 12. In use, a cliniciancan insert bi-planar instrument 10 into the joint space between firstmetatarsal 210 and medial cuneiform 222 as well as between firstmetatarsal 210 and second metatarsal 212. The clinician can then insertbone preparation guide 30 on spacer body 12 of the instrument, e.g., byaligning opening 38 with the portion of spacer body 12 projectingdorsally from the joint space. Alternatively, as noted above, bonepreparation guide 30 and bi-instrument 10 may be pre-assembled (e.g.,removably coupled together or permanently and fixedly joined together)such that inserting bi-planar instrument 10 into the joint space betweenadjacent bones simultaneously positions bone preparation guide 30 overone or more bones to be prepared.

In the illustrated example, bone preparation guide 30 extends from afirst end positioned over first metatarsal 210 and a second endpositioned over medial cuneiform 222. One or both ends of the body candefine one or more fixation apertures configured to receive fixationpin(s) for securing bone preparation guide 30 to one or more bones.

Bone preparation facilitated by bone preparation guide 30 can be useful,for instance, to facilitate contact between leading edges of adjacentbones, separated by a joint, or different portions of a single bone,separated by a fracture, such as in a bone alignment and/or fusionprocedure. A bone may be prepared using one or more bone preparationtechniques. In some applications, a bone is prepared by cutting thebone. The bone may be cut transversely to establish a new bone endfacing an opposing bone portion. Additionally or alternatively, the bonemay be prepared by morselizing an end of the bone. The bone end can bemorselized using any suitable tool, such as a rotary bur, osteotome, ordrill. The bone end may be morselized by masticating, fenestrating,crushing, pulping, and/or breaking the bone end into smaller bits tofacilitate deformable contact with an opposing bone portion.

During a surgical technique utilizing bi-planar instrument 10, a bonemay be moved from an anatomically misaligned position to an anatomicallyaligned position with respect to another bone. Further, both the end ofthe moved bone and the facing end of an adjacent end may be prepared forfixation. In some applications, the end of at least one of the movedbone and/or the other bone is prepared after moving the bone into thealigned position. In other applications, the end of at least one of themoved bone and/or the other bone is prepared before moving the bone intothe aligned position. In still other applications, the end of one of themoved bone and the other bone is prepared before moving the bone intothe aligned position while the end of the opposite facing bone (eitherthe moved bone or the other bone) is prepared after moving the bone intothe aligned position.

Movement of one bone relative to another bone can be accomplished usingone or more instruments and/or techniques. In some examples, bonemovement is accomplished using a bone positioning device, e.g., thatapplies a force through one or more moving components to one bone,causing the bone to translate and/or rotate in response to the force.This may be accomplished, for example, using a bone positioning guidethat includes a bone engagement member, a tip, a mechanism to urge thebone engagement member and the tip towards each other, and an actuatorto actuate the mechanism. Additionally or alternatively, bone movementmay be accomplished using a compressor-distractor by imparting movementto one bone relative to another bone as the compressor-distractor ispositioned on substantially parallel pins, causing the pins to move outof their substantially parallel alignment and resulting in movement ofthe underlying bones in one plane (e.g., frontal plane, sagittal plane,transverse plane), two or more planes, or all three planes. As yet afurther addition or alternative, a clinician may facilitate movement byphysically grasping a bone, either through direct contact with the boneor indirectly (e.g., by inserting a K-wire, grasping with a tenaculum,or the like), and moving his hand to move the bone.

When used, the clinician can insert bi-planar instrument 10 betweenfirst metatarsal 210 and second metatarsal 212 and between firstmetatarsal 210 and medial cuneiform 222 (or other adjacent bones, whennot performing a first metatarsal realignment) at any time prior tomoving the first metatarsal (e.g., by actuating a bone positioning guideor otherwise manipulating the bone). In one embodiment, the clinicianprepares the joint being operated upon to release soft tissues and/orexcise the plantar flare from the base of the first metatarsal 210.Either before or after installing an optional bone positioning guideover adjacent bones, the clinician inserts the instrument 10 at thejoint between the first metatarsal and the second metatarsal and at thejoint between the first metatarsal and medial cuneiform. The cliniciancan subsequently actuate bone positioning guide 20 (e.g., when used). Asdistal portion of first metatarsal can move toward the second metatarsalin the transverse plane to close the IMA, thereby pivoting a proximalportion of the first metatarsal about fulcrum body 14 and reducing theIMA between the first metatarsal and the second metatarsal. The use offulcrum body 14 can minimize or eliminate base compression betweenadjacent bones being operated upon.

The clinician can additionally engage bone preparation guide 30 withspacer body 12 and use the bone preparation guide to prepare an end offirst metatarsal 210 and an end of medial cuneiform 222. The clinicianmay prepare the ends of one or both bones before or after moving thefirst metatarsal in one or more planes (e.g., using bone preparationguide 30). In either case, the clinician may optionally provisionallyfixate the moved position (e.g., by inserting a k-wire or other fixationelement) into first metatarsal 210 and an adjacent bone (e.g., secondmetatarsal 212, medial cuneiform 222). The clinician can remove bonepositioning guide 20 and bi-planar instrument 10 from the foot, e.g.,before or after optionally provisionally fixating. In either case, theclinician may permanently fixate the prepare bone ends, causing theprepared bone ends to fuse together.

In one example technique, after customary surgical preparation andaccess, a bone preparation instrument can be inserted into the joint(e.g., first tarsal-metatarsal joint) to release soft tissues and/orexcise the plantar flare from the base of the first metatarsal 210.Excising the plantar flare may involve cutting plantar flare off thefirst metatarsal 210 so the face of the first metatarsal is generallyplanar. This step helps to mobilize the joint to facilitate a deformitycorrection. In some embodiments, the dorsal-lateral flare of the firstmetatarsal may also be excised to create space for the deformitycorrection (e.g., with respect to rotation of the first metatarsal). Incertain embodiments, a portion of the metatarsal base facing the medialcuneiform can be removed during this mobilizing step.

An incision can be made and, if a bone positioning instrument is goingto be used, one end (e.g., a tip) of a bone positioning guide 20inserted on the lateral side of a metatarsal other than the firstmetatarsal 210, such as the second metatarsal 212. The tip can bepositioned proximally at a base of the second metatarsal 212 and a thirdmetatarsal 294 interface.

Before or after attaching the optional bone positioning guide 20, theclinician can insert bi-planar instrument 10 into the joint. Theclinician can position spacer body 12 into the joint space between firstmetatarsal 210 and medial cuneiform 222 while simultaneously positioningfulcrum body 14 in the joint space between first metatarsal 210 andsecond metatarsal 212.

When bi-planar instrument 10 includes bridge member 16, the bridgemember can be positioned in contact with a proximal-lateral corner offirst metatarsal 210, helping to appropriately position spacer body 12and fulcrum body 14 relative to each other. For example, bridge member16 may position spacer body 12 substantially centered or on a lateralhalf of the joint space between first metatarsal 210 and medialcuneiform 222. Bridge member 16 may further position fulcrum body 14 inthe notch between first metatarsal 210 and second metatarsal 212 at thebase of the metatarsals (e.g., adjacent respective cuneiform). Fulcrumbody 14 can provide a point about which first metatarsal 210 can rotateand/or pivot while helping minimize or avoid base compression betweenthe first metatarsal and the second metatarsal.

In applications utilizing bone positioning guide 20, one or more movablefeatures of the bone positioning guide can be moved to reduce the angle(transverse plane angle between the first metatarsal and the secondmetatarsal) and rotate the first metatarsal about its axis (frontalplane axial rotation). The first metatarsal 210 can be properlypositioned with respect to the medial cuneiform 222 by moving a boneengagement member of bone positioning guide 20 with respect to a tip ofthe bone positioning guide. In some embodiments, such movementsimultaneously pivots the first metatarsal with respect to the cuneiformand rotates the first metatarsal about its longitudinal axis into ananatomically correct position to correct a transverse plane deformityand a frontal plane deformity. Other instrumented and/ornon-instrumented approaches can be used to adjust a position of firstmetatarsal 210 relative to medial cuneiform 222. Thus, otherapplications utilizing bi-planar instrument 10 may be performed withoututilizing bone positioning guide 20 and/or using a bone positioningguide having a different design than the specific example illustratedherein.

Independent of whether bone positioning guide 20 is used, an exampletechnique may include positioning bone preparation guide 30 over spacerbody 12 as shown in FIG. 6 (in instances in which the bone preparationguide is not integral with the spacer body). A portion of spacer body 12projecting dorsally from the joint space between first metatarsal 210and medial cuneiform 222 can be received in opening 38 of bonepreparation guide 30. One or more fixation pins can be inserted intoapertures of the bone preparation guide 30 to secure the guide to thefirst metatarsal 210 and the medial cuneiform 222. When bone preparationguide 30 is preassembled with bi-planar instrument 10 (e.g., removablecoupled thereto or fixedly and permanently coupled thereto), insertionof bi-planar instrument 10 into the joint spaces can simultaneouslyposition one or more guide surfaces of bone preparation guide 30 overone or more bone surfaces to be prepared (e.g., cut) using the guidesurface(s).

In some applications, the end of the first metatarsal 210 facing themedial cuneiform 222 can be prepared with a tissue removing instrumentguided by a guide surface of bone preparation guide 30 (e.g., insertedthrough a slot defined by a first guide surface and a first facingsurface). In some embodiments, the first metatarsal 210 end preparationis done after at least partially aligning the bones, e.g., by actuatingbone positioning guide 20 or otherwise moving the first metatarsal butafter preparing the end of first metatarsal 210. In other embodiments,the first metatarsal 210 end preparation is done before the alignment ofthe bones.

In addition to preparing the end of first metatarsal 210, the end of themedial cuneiform 222 facing the first metatarsal 210 can be preparedwith the tissue removing instrument guided by a guide surface of bonepreparation guide 30 (e.g., inserted through a slot defined by a secondguide surface and a second facing surface). In some embodiments, themedial cuneiform 222 end preparation is done after the alignment of thebones. In yet other embodiments, the medial cuneiform 222 endpreparation is done before the alignment of the bones. In embodimentsthat include cutting bone or cartilage, the cuneiform cut and themetatarsal cut can be parallel, conforming cuts, or the cuts can beangled relative to each other. In some examples, a saw blade can beinserted through a first slot to cut a portion of the medial cuneiformand the saw blade can be inserted through a second slot to cut a portionof the first metatarsal.

When bone preparation guide 30 is separable from bi-planar instrument10, any angled/converging pins can be removed and the bone preparationguide 30 can be lifted off substantially parallel first and second pinsalso inserted into the bones (or all fixation pins can be removed).Bi-planar instrument 10 (or at least spacer body 12 of the instrument)can removed from the foot. In some examples, a compressor-distractor ispositioned down over the parallel pins remaining in the bones orotherwise attached to the bones.

In applications where bone positioning guide 20 is utilized, the bonepositioning guide may be removed before or after bone preparation guide30 is removed and, when used, a compressor-distractor is installed. Ineither case, in some examples, a temporary fixation device such as anolive pin, k-wire, or other fixation structure may be used to maintainthe position of the underlying bones (e.g., first metatarsal 210relative to medial cuneiform 222), e.g., while bone preparation guide 30is removed and, optionally, a compressor-distractor is installed and/orduring permanent fixation.

When a compressor-distractor is pinned to underlying bones (e.g., firstmetatarsal 210 and medial cuneiform 222), the compressor-distractor maybe actuated to distract the underlying bones. With the underlying bonesdistracted, the clinician may clean or otherwise prepare the spacebetween the bones and/or the end face of one or both bones. Theclinician may clean the space by removing excess cartilage, bone, and/orother cellular debris that may natively exist or may have been createdduring the bone preparation step that may inhibit infusion.

Independent of whether the clinician utilizes compressor-distractor 100to distract the underlying bones for cleaning, the clinician can engagethe compressor-distractor to compress the first metatarsal toward themedial cuneiform.

With the end faces pressed together (optionally via actuation of acompressor-distractor), the clinician may provisionally and/orpermanently fixate the bones or bones portions together. For example,one or more bone fixation devices can be applied across the joint and tothe two bones to stabilize the joint for fusion, such as two bone platespositioned in different planes. For example, a first bone plate may bepositioned on a dorsal-medial side of the first metatarsal and medialcuneiform and a second bone plate positioned on a medial-plantar side ofthe first metatarsal and the medial cuneiform. In some embodiments, abone plate used for fixation can be a helical bone plate positioned froma medial side of the cuneiform to a plantar side of the first metatarsalacross the joint space. The plates can be applied with the insertion ofbone screws. Example bone plates that can be used as first bone plate310 and/or second bone plate 320 are described in US Patent PublicationNo. US2016/0192970, titled “Bone Plating System and Method” and filedJan. 7, 2016, which is incorporated herein by reference. Other types inconfigurations of bone fixation devices can be used, and the disclosureis not limited in this respect. For example, an intramedullary pin ornail may be used in addition to or in lieu of a bone plate.

Spacer body 12 and fulcrum body 14 of bi-planar instrument 10 may bepermanently coupled together (e.g., such that the spacer bodies cannotbe separated from each other without permanently destroying or modifyingthe device). Alternatively, spacer body 12 may be detachably connectedto fulcrum body 14. Such a configuration may allow spacer body 12 to beremoved from the joint space while leaving fulcrum body 14 in the jointspace (or performing other separate actions) or vice versa.

In one implementation, for example, a clinician may insert bi-planarinstrument 10 into the joint spaces and then realign one bone relativeto another bone. As the bones are realigned relative to each other,fulcrum body 14 may provide a surface along which adjacent bones canslide and/or prevent compression or base shift between adjacent bonesduring realignment. After realigning the bones relative to each other,the clinician may detach spacer body 12 from fulcrum body 14, leavingspacer body 12 in the joint space. Bone preparation guide 30 can then beinstalled over spacer body 12 to facilitate preparation of one or bothbones.

As another example, the clinician can insert bi-planar instrument 10into the joint spaces and then insert bone preparation guide 30 overspacer body 12 of the bi-planar instrument 10 (in instances in which thebone preparation guide and instrument are installed separately). Theclinician can then use bone preparation guide 30 to prepare the endfaces of one or both bones prior to subsequent realignment. With the endfaces of one or both bones suitably prepared, the clinician can removebone preparation guide 30 and detach spacer body 12 from fulcrum body14. Spacer body 12 can then be removed from the joint space, leavingfulcrum body 14 between adjacent bones for subsequent bone realignment.

FIGS. 7A and 7B are perspective and top views, respectively, of anexample configuration of bi-planar instrument 10 in which spacer body 12is detachable from and attachable to fulcrum body 14. In this example,bridge member 16 is permanently affixed to spacer body 12 and defines aninsertion end insertable into a corresponding receiving portion offulcrum body 14. Spacer body 12 and bridge member 16 can be detachedfrom fulcrum body 14 by sliding the spacer body and bridge memberlongitudinally (e.g., in a dorsal direction when inserted into thefoot), allowing the spacer body and bridge member to be detached fromthe fulcrum body.

In other configurations, bridge member 16 may be attachable to anddetachable from spacer body 12 in addition to or in lieu of beingattachable to and detachable from fulcrum body 14. In still otherconfigurations, bi-planar instrument 10 may not include a bridge memberbut instead may be configured with spacer body 12 connected directly tofulcrum body 14. In these configurations, spacer body 12 and fulcrumbody 14 can have corresponding connections that allow the two bodies tobe attachable to and detachable from each other. In general, anyfeatures described as being removably coupled to (e.g., attachable toand detachable from) each other can have complementary connectionfeatures (e.g., corresponding male and female connection features;corresponding magnetic features) that allow the features to beselectively joined together and separated from each other.

Independent of whether spacer body 12 and fulcrum body 14 are detachablefrom each other, bi-planar instrument 10 can join and position the twodifferent bodies relative to each other. The relative angle betweenspacer body 12 and fulcrum body 14 can vary depending on the desiredapplication (e.g., the anatomical location where bi-planar instrument 10is intended to be inserted and/or the anatomy of the specific patient onwhich bi-planar instrument 10 is used). In some examples, bi-planarinstrument 10 defines an interior angle between spacer body 12 andfulcrum body 14 (with or without bridge member 16) ranging from 60degrees to 120 degrees, such as from 80 degrees to 100 degrees, orapproximately 90 degrees. The angle between spacer body 12 and fulcrumbody 14 may be fixed (such that the angle is not intended to beadjustable or manipulable by a clinician during use) or may be variable(such that the angle can be adjusted by a clinician within a surgicalsuite prior to insertion and/or while inserted into a patient undergoinga procedure in which the instrument is used).

In some examples, the angle between spacer body 12 and fulcrum body 14is defined by a sharp transition, e.g., where the spacer body intersectsthe fulcrum body at the angle defined therebetween. In other examples,bi-planar instrument 10 defines a radius of curvature transitioningbetween spacer body 12 and fulcrum body 14, with the angle ofintersection defined between the faces of the two bodies. For instance,in the illustrated examples of FIGS. 5B and 7B, bi-planar instrument 10is illustrated as having a radius of curvature between spacer body 12and fulcrum body 14. Configuring bi-planar instrument 10 with a curvedtransition between spacer body 12 and fulcrum body 14 (at least on abackside of the instrument) may be useful to provide a smooth surface tohelp insert the instrument into the patient, e.g., by minimizing sharpedges that can catch on the patient's tissue during insertion.

When bi-planar instrument 10 is configured with a fixed angle betweenspacer body 12 and fulcrum body 14, the instrument may be fabricated ofa material and have a material thickness effective to substantiallyinhibit the clinician changing the angle between the two bodies duringuse of the instrument. Likewise, the instructions for use accompanyingbi-planar instrument 10 may indicate that the instrument is intended tobe used without manipulating the angle between spacer body 12 andfulcrum body 14.

In other configurations, the angle between spacer body 12 and fulcrumbody 14 may be adjustable by the clinician. For example, theinstructions for use accompanying bi-planar instrument 10 may indicatethat the clinician is able to adjust the position of spacer body 12 andfulcrum body 14 relative to each other before and/or after inserting theinstrument in the patient. In one example, bi-planar instrument 10 maybe fabricated of a material and have a material thickness effective toallow the clinician to change the angle between spacer body 12 andfulcrum body 14 during use. For example, bi-planar instrument 10 (e.g.,bridge member 16 of the instrument) may be fabricated of a malleablemetal and/or polymeric material that the clinician can manipulate underhand pressure (e.g., with or without the aid of an instrument, such as abending tool) to change the angle between spacer body 12 and fulcrumbody 14.

Additionally or alternatively, bi-planar instrument 10 may include oneor more flexible joints (e.g., rotating joints), which allow the angularposition of spacer body 12 to be adjusted relative to fulcrum body 14.As one example, spacer body 12 may be operatively connected to fulcrumbody 14 via one or more cables, allowing the angular orientation ofspacer body 12 and fulcrum body 14 to change by bending the one or morecables. As another example, spacer body 12 may be operatively connectedto fulcrum body 14 via a hinged connection, allowing the spacer body andfulcrum body to rotate relative to each other about the hinge.

FIGS. 8A and 8B are front and rear perspective views, respectively, ofan example configuration of bi-planar instrument 10 in which theinstrument is configured with a hinged connection 50 between spacer body12 and fulcrum body 14. In the illustrated configuration, spacer body 12is directedly connected to fulcrum body 14 via hinge 50. In otherimplementations, spacer body 12 may be hingedly or fixedly connected tobridge member 16 which, in turn is connected to fulcrum body 14 with orwithout a hinged connection (e.g., a hinged connection or fixedconnection). Configurating bi-planar instrument 10 with hingedconnection 50 can be beneficial to allow spacer body 12 to rotaterelative to fulcrum body 14, allowing the relative angle between the twocomponents to be adjusted.

In use, the clinician can adjust the angle between spacer body 12 andfulcrum body 14 prior to, while, and/or after being inserting into jointspaces of a patient. This can allow the angle between spacer body 12 andfulcrum body 14 to be adjusted based on the needs of the condition beingtreated and/or specific anatomy of the patient undergoing the procedure.The clinician can rotate spacer body 12 and fulcrum body 14 relative toeach other about hinge 50 prior to and/or after preparing one or bothend faces of the bones defining a joint space into which spacer body 12is to be inserted, as discussed above.

In some configurations, spacer body 12 and fulcrum body 14 can rotaterelative to each other about an unbounded range from rotation (e.g.,from a first position in which the inner face of spacer body 12 contactsthe inner face of fulcrum body 14 to a second position in which theouter face of the spacer body contacts the outer face of the fulcrumbody). In other configurations, spacer body 12 and fulcrum body 14 canrotate relative to each other within a bounded range of rotation. Forexample, bi-planar instrument 10 may include one or more rotation stopsthat limit the extent of rotation between spacer body 12 and fulcrumbody 14.

FIGS. 9A-9D illustrate example relative rotational positions betweenspacer body 12 and fulcrum body 14 of bi-planar instrument 10. FIG. 9Aillustrates spacer body 12 extending perpendicularly (at a +90 degreeangle) relative to fulcrum body 14. FIG. 9B illustrates spacer body 12positioned at an acute angle with respect to fulcrum body 14. FIG. 9Cillustrates spacer body 12 positioned at an obtuse angle relative tofulcrum body 14. Further, FIG. 9D illustrates spacer body 12 extendingin an opposite perpendicular direction (at a −90 degree angle) relativeto fulcrum body 14.

As shown in FIGS. 9A-9D, spacer body 12 may be configured to rotatethrough an arc of rotation greater 90 degrees, such as an arc ofrotation of at least 180 degrees. For example, spacer body 12 may rotaterelative to fulcrum body 14 about axis of rotation defined by hinge 50from defining an angle of at least +45 degrees with respect to fulcrumbody 14 to −45 degrees with respect to the fulcrum body. As a result,the position of spacer body 12 and fulcrum body 14 may be reversable.This can be useful to allow a single instrument 10 to be used on boththe right foot and the left foot of a patient. The position of spacerbody 12 can be rotated (e.g., approximately 180 degrees) depending onwhether instrument 10 is intended to be used on a right foot or leftfoot.

As discussed above, bi-planar instrument 10 includes spacer body 12.Spacer body 12 can be sized and shaped to be positioned in a spacebetween two bone portions, such as a joint space between adjacent bones(e.g., a TMT joint between a metatarsal and cuneiform). Spacer body 12may include a first portion insertable into the space between adjacentbone portions and a second portion that projects above the space betweenthe bone portions. The second portion projecting above the space can becoupled to a surgical instrument, such as a bone preparation guide, tocontrol positioning of the surgical instrument over the bone portionsdefining the space into which spacer body 12 is inserted.

To engage the surgical instrument (which will subsequently be describedwith reference to bone preparation guide 30 for purposes of discussion)with spacer body 12, the surgical instrument can have a receivingopening configured to receive the portion of spacer body 12 projectingabove the joint space into which the spacer body is inserted.Accordingly, the receiving opening and the spacer body can be sized andshaped relative to each other to allow the spacer body to be insertedinto and/or through the receiving opening of the surgical instrument. Insome configurations, the receiving opening of the surgical instrument issized to conform to the size of the spacer body 12 to be insertedtherein (e.g., such that there is little or no relative movement betweenthe spacer body and surgical instrument, once the spacer body isinserted into the surgical instrument). In other configurations, thesurgical instrument may be sized to allow relative movement between thespacer body and surgical instrument, even once the spacer body isinserted into the receiving opening of the surgical instrument.

FIGS. 10A-10C are illustrations of an example system that includesbi-planar instrument 10 and bone preparation guide 30, where the bonepreparation guide is configured to move relative to the spacer body ofthe bi-planar instrument. FIGS. 10A and 10B are perspective and topviews, respectively, showing the spacer body 12 of bi-planar instrument10 inserted into receiving opening 38 of bone preparation guide 30 at afirst position. FIG. 10C is a top view showing the spacer body 12 ofbi-planar instrument 10 inserted into receiving opening 38 of bonepreparation guide 30 at a second position, which is moved in thetransverse plane relative to the first position.

As shown in the examples of FIGS. 10A-10C, opening 38 of bonepreparation guide 30 is sized is larger than the portion of spacer body12 received in the opening in one or more dimensions (e.g., only one).In particular, in the illustrated example, opening 38 of bonepreparation guide 30 is sized to facilitate linear movement of bonepreparation guide 30 relative to spacer body 12 in the transverse plane,e.g., when installed over a TMT joint. Opening 38 of bone preparationguide 30 has a region 52 that is longer than a length of spacer body 12inserted into the opening. As a result, bone preparation guide 30 canslide relative to spacer body 12, while the spacer body projects upwardthrough the opening. This can be useful to allow the clinician toreposition one or more guide surfaces 34, 36 of the bone preparationguide relative to one or more bone ends to be prepared, even once thebone preparation guide is installed on the spacer body inserted into thejoint space.

FIGS. 10A and 10B illustrate bone preparation guide 30 translated to alateral-most extent (when positioned on a foot), such that the region 52of opening 38 that is larger than spacer body 12 is located on thelateral side of the spacer body. FIG. 10C illustrates bone preparationguide 30 translated to a medial-most extent (when positioned on a foot),such that the region 52 of opening 38 that is larger than spacer body 12is located on the medial side of the spacer body. The clinician can alsomove bone preparation guide 30 to one or more intermediate positions inthe region 52 of opening 38 that is larger than spacer body 12 is splitbetween the medial and lateral sides of spacer body 12.

In some configurations, opening 38 is sized relative to the size ofspacer body 12 such that the bone preparation guide can translate adistance of at least 0.5 mm relative to spacer body 12, such as at least1 mm, at least 2 mm, or at least 5 mm. For example, opening 38 may besized relative to the portion of spacer body 12 to be received thereinto be from 0.5 mm to 25 mm longer than a length of the spacer body, suchas from 1 mm to 10 mm longer. This can allow from 0.5 mm to 25 mm ofrelative movement between the bone preparation guide and spacer body,such as from 1 mm to 10 mm of relative movement. When bone preparationguide 30 is installed over a TMT joint, the bone preparation guide canbe moved relative to spacer body 12 in the transverse plane (in a medialto lateral direction) utilizing the extra length of opening 38 relativeto the size of the spacer body.

In some examples, opening 38 of bone preparation guide 30 is configured(e.g., sized and/or shaped) relative to spacer body 12 to allow relativemovement between the bone preparation guide and spacer body in thefrontal plane and/or sagittal plane, in addition to or in lieu ofallowing relative movement in the transverse plane. In other examples,spacer body 12 and bone preparation guide 30 are configured to inhibitmovement relative to each other in one or more planes. Spacer body 12and bone preparation guide 30 may be configured to inhibit movementrelative to each other in one or more planes by sizing and/or shapingthe two features relative to each other to prevent or restrict movementin the one or more planes.

With further reference to FIGS. 8A and 8B, bi-planar instrument 10 isillustrated as including a shelf 54 projecting outwardly from aremainder of spacer body 12. Shelf 54 may be a region of increasedthickness relative to the remainder of spacer body 12. Shelf 54 mayextend outwardly from a remainder of spacer body 12 from one side of thespacer body (e.g., a front face) or multiple sides of the spacer body(e.g., a front face and a rear face), as illustrated in the examples ofFIGS. 8A and 8B. Shelf 54 may be located above the portion of spacerbody that is insertable into the joint space between adjacent bones. Inother words, shelf 54 may be located on the portion of spacer body 12that is insertable into opening 38 of bone preparation guide 30. Byconfiguring spacer body 12 with shelf 54, the increased thickness ofspacer body 12 in the region of shelf 54 may prevent or eliminaterelative movement between the spacer body and bone preparation guide inthe frontal and/or sagittal planes (when installed on a foot). As aresult, bone preparation guide 30 may translate relative to spacer body12 in a transverse plane direction but may be in a substantially fixedorientation relative to the spacer body in the frontal and/or sagittalplanes.

In the illustrated example of FIGS. 8A and 8B, bi-planar instrument 10is also illustrated as having a protrusion 56 extending outwardly fromone or both faces of spacer body 12. Protrusion 56 can form a bullseye(e.g., an X or T-shaped intersection) when viewing spacer body 12 fromabove. This can be useful when visualizing spacer body 12 underfluoroscopy to help the clinician interpret where the spacer body islocated in the joint space and/or relative to bone preparation guide 30.

While bi-planar instrument 10 has generally been described as beinguseful for insertion into a space between opposed bone endstransitioning into an intermetatarsal space, the instrument may be usedin any desired application and the disclosure is not limited in thisrespect. For example, bi-planar instrument 10 may be positioned betweendifferent bone portions and/or inserted into different joint space(s)than those expressly discussed above. Further, while bi-planarinstrument 10 has generally been described with spacer body 12configured to be positioned in a first joint space and fulcrum body 14configured to be positioned in second joint space intersecting with andangled relative to the first joint space, the bi-planar instrument canbe used with only one of spacer body 12 and fulcrum body 14 positionedin a joint space (and/or positioned between different bone portions).

As one example application, bi-planar instrument 10 may be utilized in atotal ankle replacement procedure. One body (e.g., spacer body 12 orfulcrum body 14) can be inserted between the talus and the tibia in thecoronal plane and parallel to the frontal plane. The other body can beinserted between the tibia and the talus in the sagittal plane on themedial side or between the fibula and the talus on the lateral side.

As another example application, bi-planar instrument 10 can be utilizedin a total knee replacement procedure. One body (e.g., spacer body 12 orfulcrum body 14) can be inserted between the tibia and femur and theother body positioned around either the medial or lateral condyle of thefemur or the tibial plateau of the tibia to align a cut guide with theaxis of the femur or tibia.

As still a further example application, bi-planar instrument 10 can beutilized in a total elbow replacement procedure. One body (e.g., spacerbody 12 or fulcrum body 14) can be inserted between the ulna and humerusfor either an ulnar or radial resection. The other body can bepositioned around either the medial or lateral side of the bone (ulna orhumerus) to set an angle of cut on either bone.

Various examples have been described. These and other examples arewithin the scope of the following claims.

1. A bi-planar instrument for a bone cutting and joint realignmentprocedure, the instrument comprising: a spacer body configured to beinserted into a joint space between a metatarsal and an opposedcuneiform of a foot; and a fulcrum body coupled to the spacer body, thefulcrum body being configured to be inserted in an intermetatarsal spacebetween the metatarsal and an adjacent metatarsal.
 2. The instrument ofclaim 1, wherein: the spacer body defines a length configured to beinserted into the joint space, a thickness configured to extend betweenthe metatarsal and the opposed cuneiform, and a width configured toextend in a medial to lateral direction across at least a portion of thejoint space; and the fulcrum body defines a length configured to beinserted into the intermetatarsal space, a thickness configured toextend between the metatarsal and the adjacent metatarsal, and a widthconfigured to extend in a proximal to a distal direction along the foot.3. The instrument of claim 1, further comprising a bridge extendingbetween the spacer body and the fulcrum body, wherein the fulcrum bodyis coupled to the spacer body via the bridge.
 4. The instrument of claim3, wherein the spacer body is configured to extend in a first plane ofthe foot, the fulcrum body is configured to extend in a second plane ofthe foot, and the bridge member transitions from the first plane to thesecond plane.
 5. The instrument of claim 3, wherein the bridge member isconfigured to extend from a proximal side of the metatarsal to a lateralside of the metatarsal.
 6. The instrument of claim 1, wherein an angledefined between the spacer body and fulcrum body is within a range from60 degrees to 120 degrees.
 7. The instrument of claim 1, wherein thespacer body is fixedly connected to the fulcrum body.
 8. The instrumentof claim 1, wherein the spacer body is hingedly connected to the fulcrumbody.
 9. The instrument of claim 8, wherein the spacer body isconfigured to rotate at least 180 degrees relative to the fulcrum bodyto facilitate use on both a right foot and a left foot.
 10. Theinstrument of claim 1, wherein the spacer body is detachably connectedto the fulcrum body.
 11. The instrument of claim 1, wherein the spacerbody defines a first portion configured to extend into the joint spacebetween the metatarsal and the opposed cuneiform and a second portionconfigured to extend above the joint space, the second portion beingconfigured to engage a receiving opening of a bone preparation guide.12. The instrument of claim 11, wherein the bone preparation guidedefines at least one cutting slot configured to be positioned over atleast one of the metatarsal and the opposed cuneiform.
 13. Theinstrument of claim 12, wherein the bone preparation guide defines atleast one cutting slot configured to be positioned over the metatarsaland at least one cutting slot configured to be positioned over theopposed cuneiform.
 14. The instrument of claim 11, wherein the secondportion of the spacer body is sized smaller than the receiving openingof the bone preparation guide such that the bone preparation guide canmove in at least one plane relative to the spacer body, with the spacerbody inserted into the receiving opening.
 15. The instrument of claim14, wherein the second portion of the spacer body further comprises ashelf extending outwardly from at least one of a front face and a rearface of the spacer body, the shelf restricting movement between the bonepreparation guide and the spacer body.
 16. The instrument of claim 1,further comprising a bone preparation guide permanently joined to thespacer body.
 17. The instrument of claim 16, wherein the bonepreparation guide defines at least one cutting slot configured to bepositioned over at least one of the metatarsal and the opposedcuneiform.
 18. The instrument of claim 17, wherein the bone preparationguide defines at least one cutting slot configured to be positioned overthe metatarsal and at least one cutting slot configured to be positionedover the opposed cuneiform.
 19. The instrument of claim 1, furthercomprising a handle connected to the fulcrum body, the handle projectingaway from the fulcrum body.
 20. The instrument of claim 1, wherein: themetatarsal is a first metatarsal; the opposed cuneiform is a medialcuneiform; and the adjacent metatarsal is a second metatarsal.
 21. Theinstrument of claim 1, wherein the spacer body and fulcrum body arefabricated as separate components that are subsequently connectedtogether to form a unitary instrument.